Combined priming and sparking plug.



G. G. TATE.

GOMBINED PBIMING AND SPARKING PLUG.

APPLICATION FILED MAY 2p, 1912.

1,095,244, Patented May5,1914.

WITNESSESP I INVENTOR QM jar z" ii/fou By Arron/v51 sn'rns rATENT OFFICE.

CHARLES G. TATE, OF CHICAGQ, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS, T0 UNITED MOTOR- EQUIPMENT GOMPANY, A CORPORATION OF MAINE.

COMBINED PRIMING AND SPARKING PLUG.

To all whom it may concern Be it known that I. CHARLES G. .Txrn, a citizen of the United States, residing at Chi cago, county of Cook, and State of Illinois, have invented a certain new and useful Improvement in Combined Priming and Sparking Plugs, of which the following is a specification.

My invention relates to that class of spark plugs which are designed to be used on an explosive engine. and has for its objectto provide a spark plug for use where the priming fluid consists of an explosive gaseous fluid instead of a liquid.

I am aware that there are combined priming and sparking plugs which are designed for use in introducing a liquid for priming purposes, but those with which I am familiarwould not serve the purpose for which my plug is invented. \Vhere gas under pressure is introduced into the engine, it' the mixture is too rich, it will not explode, and as a consequence the engine will not start. This occurs very frequently where the new types of starting devices employing acetylene gas are used.

My invention is designed to provide aprimer which will insure the complete mixing of the priming charge with the air in the cylinder.

It is also possible in spark plugs in which there is not a considerable portion of' the porcelain exposed, which latter feature is objectionable due to the danger of breakage, for the current to jump from the binding post to the metal part of the plug, rather than to jump across the sparking points in the interimof the cylinder.

My invention has for its further object to provide 2 special form of insulation which will prevent this occurrence.-

My means of accon'iplishingt he foregoing objects may be more readily understood by having reference to the accompanying drawings, which are hereunto annexed and are apart of this specification, in which Figure 1 is a side elevation of one of my improved spark plugs. Fig. 2 is a. vertical sectional view of the same.

Similar reference numerals refer to similar parts throughout the entire description.

As shown in the drawin s, 1 is an exterior shell preferably formed 0 metal, the lower part of which is provided with external threads 2 adapted to be screwed into the Specification of Letters Patent Patented May '5, 1914.

Application filed May 20, 1912. Serial No. 698,411.

cylinder head of the engine (not shown). A

hexagonal shoulder 3 is formed on the metal sleeve to facilitate the operation of screwing the plug into the cylinder head.

-.t is a lug which extends laterallyfrom one side of the exterior sleeve 1. This lug is provided with internal threads 5 to receive the connection trOiITthEfiiPing, which is designed to convey the priming fluid to the engine. 6 is the interior member is provided with two longitudinal passages 7 and 8. The passage 7 has mounted therein a bolt 9, the upper end of which is constructed to form a binding post 10, the lower end 11 forming one of the sparking points. The other point 15 is mounted in the end of the metal sleeve in the usual or customary manner. A shoulder 12 is provided on the bolt 9 to prevent the leakage of the pressure in the cylinder.

13 is my improved insulating cap, which should be preferably constructed. of suitable insulating fiber, which fits around the upper end of the porcelain member, its circumferential flange 16 being of sufficient height to furnish an air gap, which will be too wide for the electricity to jump. This cap serves also to protect the porcelain from accidental breakage. Practice has shown that when a plug is so equipped the porcelain will last indefinitely. Nuts of any suitable character may be used for connecting the electrical wires (not shown) to the bolt 9. As shown, a pair of hexagonal nuts are employed for this purpose.

The passage 8 is in communication with the interior of the lug 4. and is designed to lead the priming fluid to the interior of the explosion chamber.

It is a recognized fact by persons engaged in handlingor constructing devices designed of the plug, which to ei't'ect'a mixture of an injected gas with the mixture adjoining the sparking points Will be so rich that no explosion can take place.

I have discovered that Where the walls adjacent the orifice 14 are tapered, to the stantially every instance.

mounted, in the other,

While I have described a specific form of construction for the metal and porcelain parts of my plug, I would wish to be understood as not limiting myself to the pre cise construction shown, except as such limitations appear in the claims.

Having described my invention, what I regard as new and desire to secure by Letters Patent is:

1. A combined priming and sparking plug comprising an exterior shell of metal, a laterally extending lug formed on'one side thereof, an interior member formed vof porcelain,there being two longitudinal passages through said porcelain, there being a passage through said lug communicating with one of said longitudinal passages, a bolt one end of which flonies of this patent may be. obtained folfive cents each, by addressing the f Commissioner or rah Washington,

forms a sparking point and the other a bindthereof, an interior member formed of por- 1 celain, the upper end of which extends beyond the metal shell, there being two longitudinal passages through said porcelain, there being a passage through said lug communicating with one .of said longitudinal passages, a bolt mounted in. the other, one

forms at end of which sparking point, and the other a binding post, a hexagonal shoulder on said shell and threads out upon one end thereof, the Walls of the is in communication with the laterally ex tending lug tapering inwardly at the and adjacent the explosion chamber, a cap cl" insulating material to protect the upwardly extending portion from accidental breakage and to prevent electricity jumping to the metal shell.

In witness whereof I have signed the forcgoing specification.

CHARLES G. TA'lE. Witnesses:

K.'DoLr.nY,

C. M. BAurnersrnn.

at the passage which L 

